Danno,
I just finished installing a righting pole on my Nacra 5.5. I used a windsurfing mast and universal joint. In my opinion, installing the pole was not worth the effort. It did not allow me to right my cat solo, and it was only slightly more effective than a righting line thrown over the top hull. I used an 8 foot pole, and perhaps a 9-10' pole would have worked better, but I don't want 2' of pole sticking out the back of my cat. I only weigh 140 lbs, so perhaps the pole will work better for you.
Mike